restructure project

internal/builtins/exit.go

@@ -0,0 +1,26 @@
+package builtins
+
+import (
+	"monkey/internal/object"
+	"monkey/internal/typing"
+)
+
+// Exit ...
+func Exit(args ...object.Object) object.Object {
+	if err := typing.Check(
+		"exit", args,
+		typing.RangeOfArgs(0, 1),
+		typing.WithTypes(object.INTEGER_OBJ),
+	); err != nil {
+		return newError(err.Error())
+	}
+
+	var status int
+	if len(args) == 1 {
+		status = int(args[0].(*object.Integer).Value)
+	}
+
+	object.ExitFunction(status)
+
+	return nil
+}